m42 poor dyno results :(

[327ire]

Got my conversion dyno'd a while ago, results on my m42b18 with very poor top end power and torque. Iv just spotted an engine in my local scrappy and im wondering would it be an idea to swap them over? I think I could do it in a single day and cost about 300 euro so im seriously contemplating it.

my results;


My results vs alync205's results



So am I 27bhp short because of a bad engine? Or would i be wasting my time swapping?

current spec is;
1992 e36 318is engine + loom + intake (in an e30)
Superchips chip, (performs better than stock)
Electric fan,
Heater plate deleted,
KnN Cone Filter Cold Air
e36 exhaust down to a cherry middle box and 320i rear box

[johnl320]

My first move would be to stick the standard chip back in and retest.

[327ire]

The local dyno aint exactly local so testing isnt an easy job unfortunately. Its a proper brand name chip though, superchips - same as this guy http://www.esatclear.ie/~bpurcell/318ismods.html#chips
Its noticeably faster than the stock chip.

Some people are saying that it could be a lot of small things like a poor intake and exhaust, injectors, pump etc. Im going to do a compression test later today and see what comes up.

[hoshy]

I would have the cams checked and reset to stock timing too - it's a pretty quick job and you're quite a lot of power down - I think that could account for it.

[327ire]

Would worn cams show up mostly in the top end of the HP curve? My low end HP isnt that bad but just falls off after 4000rpm

[hoshy]

I didn't mean the were worn only. Also that the timing is incorrect. The M42 has adjustable sprockets on both cams that can slip or be prone to maladjustment.

[Cypriotgeeza]

Just looked on the "superchips" website and the price for a 318iS chip is £239 for an 8hp increase

please dont say you payed that much for it!!

[Brian28]

Are the charts power at the wheels or flywheel power?

[Gunni]

they´ll be flywheel, a NA 1.8 does not do 105nm/liter at the wheels

[327ire]

The increase is more than what they have quoted on the site, I was told closer to 15bhp from the garage that installed it but it is a bit worrying that their site quotes 8bhp! I payed about 180£ for it, I couldnt find anyone doing it cheaper at the time. Its one of the reasons that I want to fix the power issues.

[rix313]

It wont find 27hp but give it a buggering good service. Also look at getting your injectors cleaned as they will have clogged with 20 years of usage; check out Injectortune the trader on here.

Consider the E30 inlet manifold as IIRC these gave better torque then the E36's.

[eta]

Also you don't know that the dyno is accurate. Different dyno's give different figures, on a different dyno you might get 135hp. The thing to note is is the power/torque curve the right shape.

[Jon_Bmw]

My engine is down its got more power than that, the dyno is wrong.

My engine doesn't have that much power, it is overeading, the dyno is wrong.

The amount of times I hear this on the same dyno day is unreal.



There is two tests there with two different cars, one is a touch high perhaps for an iS and the other is noticeably down. I would say there is something up with the car rather than accuse the dyno of being wrong. The dyno might well be wrong, but it will be consistently wrong, rather than up and then down.

[327ire]

The dyno seems to be fairly good. They are a new garage since last year and Iv seen lots of dyno results from them that seem accurate. Iv seem other dyno results of cars with and without fans to cool the car while on the dyno and provide air through a cold air duct which do show around 10bhp of a difference. My car was actually over half way on the temp gauge when the dyno guy decided to hang up his phone and start the run. The intake temps would have been very high through the cone filter.

Im not blaming a crap dyno for the poor results, but if anyone asks me how much power the engine has id usually say 130bhp rather than the 125 on the graph.

Anyway, doesnt matter, i have a m52b28 on a pallet waiting to be installed in the same car so...